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OBJECTIVE: To assess the diagnostic test characteristics of placental weight as a clinical predictor of small-for-gestational-age (SGA) neonates. STUDY DESIGN: Placentas were weighed at 45,846 deliveries. Predictive values and likelihood ratios (LRs) were calculated assessing placental weight (lowest tertile vs. top 2 or mid/high tertiles) as a predictor of SGA both overall and by maternal age, gestational age, maternal weight, reported early pregnancy smoking, race, neonatal sex and parity. RESULTS: Although the positive predictive value (PPV) of low placental weight was poor (0.19), the negative predictive value (NPV) was high (0.97). Both NPV and LR- were powerfully predictive in women at earlier gestational ages. At gestational ages <32 weeks, LR-was 0.11, showing that among women with mid/high placental weight, the proportion with SGA (false negative) was about 1/10 that without SGA (true negative). CONCLUSION: Placental weight in the mid or upper tertile has strong NPV and LR- for delivery of an SGA neonate. Further study of the value of placental size in prediction of SGA is warranted.  相似文献   
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Both child growth and dietary diversity are poor in rural Timor‐Leste. The rainy season is associated with food scarcity, yet the association between seasonal scarcity, food diversity, and child growth is underdocumented. This study assesses the relationship between household dietary diversity and children''s standardized growth across the 2018 food‐scarce (April–May; post‐rainy period) and post‐harvest (October) seasons in the agricultural community of Natarbora, on the south‐coastal plains of Timor‐Leste. We conducted household interviews and collected anthropometric data across 98 and 93 households in the post‐rainy and post‐harvest periods, respectively. Consumed household foods were obtained via 24‐h diet recalls and were subsequently categorized into a nine‐food‐group dietary diversity score (DDS; number of different food groups consumed). The DDS was related to children''s standardized short‐term growth (z‐weight, z‐body mass index [BMI] and percent change in weight over the harvest season) via linear mixed models. Across seasons, DDS increased from 3.9 (standard deviation [SD] = 1.0) to 4.3 (SD = 1.4; p < 0.05). In the post‐rainy season, children in high DDS households had higher z‐weight than those in low DDS households and higher z‐BMI than children in medium and low DDS households. In the post‐harvest period, household DDS did not predict children''s z‐weight but predicted z‐BMI. Consumption of protein‐rich foods, particularly animal‐source foods and legumes, in low‐ and medium‐DDS households may be associated with improved child growth. While consuming more animal‐source foods in the post‐rainy season would be ideal, promoting the consumption of locally grown legumes, such as beans and pulses, may facilitate better nutritional outcomes for more children in rural Timor‐Leste.  相似文献   
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The CF and HI antibody titers to rubella and measles viruses, the CF titers to influenza A, and the HI titers to parainfluenza 1, 2, and 3 were carried out on the sera of 20 patients with childhood polymyositis and their matched controls. The titers for measles, parainfluenza 1, and influenza A were slightly higher for patients than for controls. The control group had antibody titers to rubella and parainfluenza 2 and 3 higher than or similar to those of patients. Strong patterns or significant differences for a given virus or virus group were not encountered.  相似文献   
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Up to 5% of gastrointestinal bleeds occur between the ligament of Treitz and the ileocecal valve. These patients present with occult bleeding and pose diagnostic and therapeutic challenges. Currently, an array of technology exists for diagnostic purposes, including upper and lower endoscopies, capsule endoscopy, nuclear scans, angiography, and intraoperative endoscopy. All of these modalities have advantages and disadvantages. However, the diagnostic gold standard for occult gastrointestinal bleeding does not exist. We present a case of an 18-year-old male with occult gastrointestinal bleeding to illustrate the variety of available modalities. Initially, the patient underwent upper, lower, and push endoscopies. Subsequently, he had a nuclear bleeding scan, video capsule endoscopy, and an angiogram. Ultimately, the patient had a diagnostic laparoscopy with mobilization of the terminal ileum and right colon. The bowel was exteriorized and an intraoperative endoscopy was performed through a small bowel enterotomy. Multiple arteriovenous malformations (AVMs) were ascertained and resected. This case is presented in detail and the technique of intraoperative endscopy is reviewed. The diagnostic literature regarding AVMs is also reviewed.  相似文献   
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